Abstract: Small coal mines are mostly uncertified mining. There is no mining planning, no mining maps for these mined galleries. They have the characteristics of small mining depth, complex distribution of mined areas, and extremely difficult to locate all these abandoned galleries. Locating these empty mined area distributions and their influence area have significant importance of the project. This paper presents a case history of the comprehensive geotechnical investigation and mitigation program at the abandoned mining area for a main area for a power plant. The testing program after the ground improvement show that the effect of the control measures used in the investigation and mitigation are satisfactory, and the comprehensive investigation methods used are appropriate for the exploration of the abandoned galleries of small coal mines, which can provide a strong basis for the control design and can provide a useful reference for similar projects in the future.

Key words: Small Coal Mine Gallery, Comprehensive Investigation Methods, Control Measures, Power Plant